1. Field of the Invention
The present embodiments relate to a plasma display panel, and more particularly, to a plasma display panel that displays images by generating discharges in discharge cells in response to a power supplied through a metal electrode disposed toward a surface of the plasma display panel on which images are displayed.
2. Description of the Related Art
In recent times, plasma display panels, which are expected to replace conventional cathode ray tube display devices, have received much attention. Plasma display panels display images using visible light emitted through a process in which a phosphor material formed in a predetermined pattern in a space is excited with ultraviolet rays generated by a discharge of a discharge gas in the space when a discharge voltage is applied to the electrodes.
FIG. 1 is an exploded perspective view of a conventional plasma display panel (PDP).
Referring to FIG. 1, a typical alternating current type PDP 10 includes an upper plate 50 on which images are displayed and a lower plate 60 coupled to the upper plate and parallel to the upper plate 50. Sustain electrode pairs 12 in which an X electrode 31 and a Y electrode 32 form a pair are formed on a front substrate 11 of the upper plate 50. Address electrodes 22 crossing the X and Y electrodes 31 and 32 of the front substrate 11 are disposed on a rear substrate 21 of the lower plate 60 that faces a surface of the front substrate 11 where the sustain electrode pairs 12 are disposed.
A first dielectric layer 15 in which the sustain electrode pairs 12 are buried and a second dielectric layer 25 in which the address electrodes 22 are buried are respectively formed on the front substrate 11 and the rear substrate 21. A protective layer 16 is usually formed of MgO on a rear surface of the first dielectric layer 15, and barrier ribs 30 that maintain a discharge distance between the front substrate 11 and the rear substrate 21 and prevent electrical and optical cross-talk between discharge cells are formed on an front surface of the second dielectric layer 25.
Red, green, and blue phosphor layers 26 are coated on both side surfaces of the barrier ribs 30 and on an entire surface of the second dielectric layer 25 where the barrier ribs 30 are not formed.
The X electrode 31 and the Y electrode 32 include transparent electrodes 31a and 32a, respectively, and bus electrodes 31b and 32b, respectively. A space formed by the pair of the X electrode 31 and the Y electrode 32 and the address electrodes 22 crossing the X and Y electrodes 31 and 32 is a unit discharge cell 70 which forms one discharge unit.
The transparent electrodes 31a and 32a are formed of a conductive transparent material that can generate discharges and does not interrupt the progress of light emitted from phosphor layers 26 toward the front substrate 11. The transparent material can be indium tin oxide (ITO). Also, the bus electrodes 31b and 32b are usually formed of a metal having a high electrical conductivity, and have a double layer structure comprising a black bus electrode layer (not shown) and a white bus electrode layer (not shown). The black bus electrode layer, which is located on a side of the transparent electrodes 31a and 32a, increases bright room contrast by absorbing external light, and the white bus electrode layer, which is located on a side of the discharge cell, increases brightness by preventing the absorption of visible light emitted from the discharge cells. However, to form the bus electrodes 31b and 32b made of the black and white bus electrode layers, two processes are required. Therefore, recently, the bus electrodes 31b and 32b are sometimes formed in one process by forming the black and white bus electrode layers as one unit to simplify the processes.
However, in this case, since the whiteness is reduced, the visible light generated in the discharge cells is absorbed by the one-unit type bus electrodes, and the brightness is reduced.